Category Archives: Consumers

Nanoparticles, cosmetics and sunscreens – again!

Robin Erb has a good piece on cosmetics and safe ingredients in the Detroit Free Press this week – it tackles the very limited regulation over what goes into cosmetics, but balances this with a useful perspective on consumer choice and how this in turn can drive business decisions on what is used and how.  I mention it because the issue of nanoparticles in sunscreens comes up briefly, and I am quoted on the matter.

Regular readers of this blog will know that I have been fairly vocal about the safety of nanoparticles in sunscreens.  I still contend that the weight of published evidence suggests that titanium dioxide and zinc oxide nanoparticles in sunscreens do not present a significant when the relevant products are developed and used responsibly – and that the benefits of using this technology over others may in fact outweigh any residual risk.  But I’m also aware that this isn’t a closed issue – there are niggling questions on the use of photoactive particles, on nanoparticle sunscreen applications on delicate or compromised skin, and on dermal penetration of chemicals within the nanoparticles, that all need further research.  So I was surprised to read that my mind is apparently made up here!

After talking with Robin about cosmetics, sunscreen and nanoparticles, she sent me draft of my comments to check for factual accuracy before the piece went to press.  The original text read:

“…Agreed Andrew Maynard, director of the Risk Science Center at the University of Michigan School of Public Health: “The industry seems reasonably well self-regulating.”

In his research, Maynard asked whether nanomaterials in sunscreen — the nearly molecular-sized particles that ease the lotion into our skin pores – are dangerous. His conclusion: They’re not.

“It was really surprising, to be honest,” he said.”

This was uncommonly generous of Robin by the way – many reporters will not do this (for good reason – they don’t want people interfering with the story), and in general I don’t expect it.

My response:

Hi Robin, and thanks for letting me see this – Scott’s comments are great here btw.

If you are able, could I just change one thing: instead of “In his research, Maynard asked whether nanomaterials in sunscreen — the nearly molecular-sized particles that ease the lotion into our skin pores – are dangerous. His conclusion: They’re not.”, is it possible to have something along the lines of “In his research, Maynard asked whether nanomaterials in sunscreen — the nearly molecular-sized particles that protect the skin from the sun – are dangerous. His conclusion: Not if they’re used responsibly”

It’s not as black and white admittedly, but there are still niggling uncertainties associated with the use of nanoparticles that I am on record as highlighting (as there are with other sunscreen ingredients), and it would look odd if I was quoted as saying something that seemed to contradict my usual message.

I should note at this point that, under these circumstances, my policy is to treat the reporter’s work with respect, and refrain from editing the text unless there is a compelling reason to do so.  But in this case I was concerned about the overstatement of my position on nanoparticle safety, and I thought that the technical error on the purpose of the nanoparticles being to ease the lotion into the skin pores should be addressed (in sunscreen the particles coat the skin and protect against UV exposure.  In some cosmetics, nanoparticles are used to help penetrate through the outer dead layers of skin cells – there may have been some confusion between the two here).

Robin responded back:

“Thanks for the response. No problem on tweaking the wording. I want it correct, of course.

Let me just ask this though: What would be an “irresponsible” use of sunscreen? I’m not trying to be funny – I just want to make sure the qualifier “if used responsibly” really translates for consumers.”

To which I replied:

“Understand – “responsible” can be a bit of an irresponsible blanket term :-)

Here, I mean using nanoparticles after giving possible health and environmental impacts due consideration, and doing everything possible to ensure minimal impacts and significant benefits. A bit of a mouthful, but feel free to tweak the quote. I won’t be able to respond as I’m about to board a plane back to Michigan from Denmark (hence the delay with this response) – but am sure whatever you arrive at will be fine.”

I may have been a bit generous with that last statement, as what was published on Monday came out as:

“Andrew Maynard, director of the Risk Science Center at the University of Michigan School of Public Health, agreed. “The industry seems to be reasonably well self-regulating.”

In his research, Maynard asked whether nanomaterials in sunscreen — the nearly molecule-sized particles that ease the lotion into our skin pores — are dangerous. His conclusion: They’re not.

“It was really surprising, to be honest,” he said.”

The adherence to the original text isn’t a particularly big deal, and to be fair I almost definitely didn’t express myself as clearly as I could have in the original phone interview.  But just in case you read this and thought that the book was closed on nano-sunscreens from my perspective – it’s not!

Are consumers risking skin cancer because of fears over nanoparticles in sunscreens?

This has just landed in my email in box from Craig Cormick at the Department of Industry, Innovation, Science, Research and Tertiary Education in Australia, and I thought I would pass it on given the string of posts on nanoparticles in sunscreens on 2020 Science over the past few years:

At Australia’s International Conference on Nanoscience and Nanotechnology (ICONN 2012) earlier this month, the results of a public perception study were released that indicate some Australian consumers would rather risk skin cancer by not using sunscreen than use a product containing nanoparticles.  This despite increasing evidence that nanoparticles in sunscreens do not present a significant risk to health. The study was complimented by tests conducted by Australia’s National Measurement Institute that suggest some sunscreens labeled as “nano free” contain nanostructured material.

According to the media release on the public perceptions study,

“An online poll of 1,000 people, conducted in January this year, shows that one in three Australians had heard or read stories about the risks of using sunscreens with nanoparticles in them,” Dr Cormick said.

“Thirteen percent of this group were concerned or confused enough that they would be less likely to use any sunscreen, whether or not it contained nanoparticles, putting them selves at increased risk of developing potentially deadly skin cancers.

“The study also found that while one in five respondents stated they would go out of their way to avoid using sunscreens with nanoparticles in them, over three in five would need to know more information before deciding.”

A news release sent out a couple of weeks ago to coincide with ICONN 2012 also noted

Scientists from Australia’s National Measurement Institute and overseas collaborators reported on a technique using the scattering of synchrotron light to determine the sizes of particles in sunscreens. They found that some commercial sunscreens that claim to be ‘nano-free’ do in fact contain nanostructured material. The findings highlight the need for clear definitions when describing nanomaterials.

This study allegedly led to Friends of the Earth Australia removing their Safe Sunscreen Summer Guide 2011-2012 from the web – a guide which advises against using nanoparticle-containing sunscreens – until further information is available. The guide’s website currently states:

“Doubt has been cast over the accuracy of the nano status of some sunscreen brands in our guide. It appears that some companies may have been deceived as to the nano-content of their products. We are working flat-out to get a resolution to this matter.

We advise people to continue to be sun safe when spending time in the sun: seek shade, wear protective clothing, a hat and sunglasses and use sunscreen.

This page will be updated as soon as possible.

Thanks for your patience.”

While early questions concerning the possible dangers of using nanoparticle-containing sunscreens were legitimate given the state of science ten years ago, research over the intervening years has failed to substantiate concerns (see this review for example). Despite this, this latest opinions survey indicates that people may be at risk of placing themselves in greater danger because of concerns that continue to be articulated.  Although it’s always hard to estimate how answers to questions like the ones asked here translate into actual actions, the survey does beg the questions – at what point does asking questions stimulate actions that lead to greater risks; and how should the public dialogue around a speculative risk respond to new evidence as it emerges?

Full details of the sunscreen perceptions and awareness survey can be found here.

Also worth reading: The safety of nanotechnology-based sunscreens – some reflections

Responsible development of… Unobtanium?

I thought I’d post this spoof presentation for the fun of it on the responsible development of “unobtainium”, which seems to have some remarkable similarities with some other emerging technologies:

If you’re a little mystified, blame David Berube – who encouraged the initial idea, and embellished it in his own presentation at a recent conference on another – but entirely unrelated – technology: nanotechnology.
While this is all rather facetious, there are some important points buried in the presentation, that touch on issues surrounding speculative hype, exponential extrapolation, and analysis unencumbered by evidence.
As a final word, David thought it a great lark writing about a mythical material called unobtanium, but was tickled pink to discover that there are some people who take this seriously. Here’s some stuff he dug up:
  • First there’s the Wikipedia page dedicated to the material.
  • Then, a Google Scholar search currently returns around 145 hits for the search term “unobtainium”.
  • In 1990, Misra and Mohan wrote a piece titled “Towards unobtainium [new composite materials for space applications]” in Aerospace Composites and Materials. (Vol. 2, pp. 29-32. Nov.-Dec. 1990).
  • And in 2010 Wired Magazine ran an on-line story on a congressional hearing on unobtanium.  Sadly, the hearing was only on rare earth elements – no mention of unobtanium on Capitol Hill – but the unobtanium story got some traction.
Which just goes to show that no matter how hard we try to be make up weird stuff, the things people take seriously are almost always weirder!

Australian Education Union advises against using nanoparticle-based sunscreens in schools

Last week, the Victoria branch of the Australian Education Union (AEU) passed a resolution recommending that “workplaces use only nanoparticle-free sunscreen” and that sunscreens used by members on children are selected from those “highlighted in the Safe Sunshine Guide produced by Friends of the Earth” as being nano-free.  The AEU also resolved to provide the Friends of the Earth Safe Sunscreen Guide and Recommendations to all workplaces their members are associated with.  Given what is currently known about sunscreens – nano and otherwise, I can’t help wonder whether this is an ill-advised move.

The debate over the safety or otherwise of nanoparticle-containing sunscreens has been going on for over a decade now.  Prompted by early concerns over possible penetration through the skin and into the body of the nanosized titanium dioxide and/or zinc oxide particles used in these products – and potential adverse impacts that might result – there has been a wealth of research into whether these small particles can actually get through the skin when applied in a sunscreen.  And the overall conclusion is that they cannot.  There have been a small number of studies that demonstrate that, under specific conditions, some types of nanoparticle might penetrate through the upper layers of the skin.  But the overwhelming majority of studies have failed to find either plausible evidence for significant penetration, or plausible evidence for adverse health impacts – a body of evidence that led the Environmental Working Group to make an about-face from questioning the use of nanoparticle-containing sunscreens to endorsing them in 2010.

So why is the AEU now advising against their use?  And why are they advocating selecting sunscreens based on a document that does not provide evidence-based advice on efficacy or safety – and may end up leading to decisions that increase the risk of sun-related skin damage in children (more on this below)? (Update 5/25/11 – see notes below)

In part, the answer lies in the uncertainty inherent in proving anything safe.  It’s not too difficult to show that something is unlikely to be harmful, or is probably safe.  But proving something is absolutely safe under all conditions of use is simply not possible – there is always some room for doubt.  This is why decisions on health risks are typically based on plausible risk and weight of evidence – evaluating the most reasonable and defensible interpretation of the data, and not basing decisions on speculation and fantasy.

With the use of nanoparticles in sunscreens, the weight of evidence is that they are safe and effective – and may be safer and more effective than a number of non-nanoparticle alternatives as they work by coating the skin rather than being absorbed into it.  That said, it’s always prudent to check whether anything has been missed with a relatively new technology like this, and so research is ongoing just to make doubly sure that the nanoparticles currently being used stay on top of the skin, and that manufacturers are using the safest possible types of nanoparticles.

But there is another reason I suspect why the ASU have released this advice, and that is due to a study using human volunteers that was published last year.

In this study by Brian Gulson and colleagues, sunscreens were formulated with zinc oxide particles made from a stable isotope of zinc that doesn’t occur in great abundance naturally: Zn-68. Using Zn-68 as a tracer, they were able to tell whether zinc from the applied sunscreen entered the bodies of the volunteers, and ended up in their blood and urine.

The detected presence of Zn-68 in the urine and blood of volunteers was used by Friends of the Earth Australia to renew their recommendations against using nanoparticle-containing sunscreens until more is known about their safety in.  And given the ASU’s reliance on the Friends of the Earth document, it seems to have influenced their decision to recommend not using nanoparticle-containing sunscreens.

But what does the Gulson study actually conclude?  In a nutshell, the researchers showed that:

  • Small amounts of zinc from sunscreens containing any form of zinc oxide particles tested found their way into the blood and urine of volunteers.
  • The amounts of zinc entering the body over the five day study were miniscule – around one thousandth of the concentration of zinc already in the volunteers’ bloodstream, and around one thousandth of the amount of zinc recommended in a person’s daily diet.
  • Women in the test generally showed higher uptakes of zinc than men.
  • Zinc levels in blood associated with the sunscreen peaked some days after applications ended, suggesting the zinc or zinc oxide was stored somewhere in or on the body and slowly released.
  • For men, zinc uptake from sunscreens was independent of particle size.  For women, zinc uptake was greater from the sunscreens containing smaller particles.

So did the particles go through the skin?  The study only showed that the zinc passed through the skin, and did not provide any evidence of particle penetration.  Two possible explanations for this are that the particles penetrated and entered the bloodstream, or that the applied particles dissolved, and that it was dissolved zinc that was penetrating into the body.

Out of the two possibilities, there is minimal evidence for particle penetration being a plausible mechanism. On the other hand, zinc oxide is sparingly soluble, and under the acid-conditions of the outer layers of the skin the particles would have readily released zinc ions.  The weight of evidence to date therefore strongly supports dissolution of the particles and subsequent dermal penetration of dissolved zinc.  This is supported by the similarity in uptake seen in men of zinc for two different sizes of zinc oxide particles.

In other words, this study provides neither compelling evidence that nanoparticles in sunscreens can pass through the skin, or that they can lead to worrying internal exposure to harmful materials.  It did indicate on the other hand that any sunscreen containing zinc oxide will lead to zinc entering the body via the skin – including sunscreens that rely on large zinc oxide particles.

And this is where it is worth returning to the Friends of the Earth recommendations.

The Friends of the Earth Safe Sunscreen Guide recommends:

Use a nano-free zinc-based SPF 30+ broad spectrum sunscreen in conjunction with protective clothing, a broad-brimmed hat, sunglasses and shade to stay sun safe.

It goes on to list sunscreens that are “nano and chemical free”, “may use nano” and “use nano” (based on information from manufacturers and assumptions from Friends of the Earth).

Passing over the fact that Friends of the Earth are advocating the use of sunscreens that demonstrate the same behavior – zinc penetration through the skin into the body – as the sunscreens they recommend people don’t use, it’s hard to understand how this document provides an authoritative and evidence-based guide for the use of sunscreens on school children – as suggested by AEU.

For a start, this is a document that is specifically concerned with nanoparticle-containing sunscreens, and is not aimed at providing advice on selecting sunscreens as a whole based on their safety and efficacy.  It is advocating a specific course of action, and is not a tool for taking informed action. And in this respect alone it is a questionable document to be distributing to school workers. But it gets worse.

The sunscreens listed in the document are listed solely with respect to their nanoparticle content.  There is no – let me repeat that no – information on how effective these sunscreens are at protecting against UVA and UVB, and what the specific safety issues associated with their use are (update 5/25/11 – see notes below).  What is more, the top tier products – those that appear to be most strongly endendorsed by Friends of the Earth – also claim to be “free of UV-absorbing chemicals”.  In other words, this is a document that appears to be endorsing the use of products that do not necessarily protect against ultraviolet light. (Update 5/25/11 – see notes below).

To be fair to Friends of the Earth – and this is not a critique of their document so much as a questioning of its use as authoritative guidance – they do recommend the use of sunscreens providing substantial UV protection that are (presumably) based on large zinc oxide particles.  But if school workers were to base their choice of what to slather onto kids on the list of products, rather than the one sentence top level recommendation, they could well be applying sunscreens that do not protect against skin damage.

And this is my greatest concern here – by advocating the use of the Friends of the Earth document, AEU could actually be endangering the health of children in the care of their members. (Update 5/25/11 – see notes below)

Of course, there are important issues to grapple with here – including how appropriate sunscreens should be selected for use on children, irrespective of the technology being used.  But surely these selections should be based on the best possible evidence that is focused on what is most appropriate for the children, and not on an action campaign by an advocacy group, no matter how well intentioned.

Update, 5/25/11:  As clarified by Georgia Miller of Friends of the Earth Australia in the comments below, the sunscreens listed in the top tier of the Friends of the Earth document are all – as far as I can tell – marketed as offering SPF 30 + protection.  This is something that I do not think is explicitly clear in the document, and the heading of “nano and chemical-free”, clarified with “products also free of UV-absorbing chemicals” raises an obvious question to the naive reader over whether these products do indeed offer significant protection.  I also continue to have serious reservations over the use of a document designed to steer people away from nanoparticle-containing sunscreens as authoritative advice on sunscreen protection for children, given it’s lack of independent testing and evaluation of all significant factors that might affect choice in a given situation.  Nevertheless, given the protection ratings of the recommended sunscreens, I have on reflection retracted the statements made in regard to the protection offered above.

Looking for the nanotechnology in your life? There’s an app for that!

Okay so it’s more of a list of nanotech-enabled products than a lifestyle tool, but at the Project on Emerging Nanotechnologies, we’ve just released an iPhone version of our surprisingly successful web-based nanotech Consumer Products Inventory.


With findNano, it’s a piece of cake to search or browse through the 1000+ manufacturer-identified nanotechnology-enabled products in the inventory, directly from an iPhone or iPod Touch.  And the really cool part – if you come across something that isn’t in the inventory that you think should be, you can simply take a photo and email it to us directly from the app.  And if it passes muster, we’ll add it to the list.

The best way to discover what findNano is all about is probably to download it and take it for a spin (it’s free).  But here’s a quick overview for the curious: Continue reading Looking for the nanotechnology in your life? There’s an app for that!

“Nano” from the 1970’s. Don Eigler, eat your heart out!

Twenty years ago, Don Eigler became the first person to manipulate and position individual atoms, making the breakthrough that many consider a pivotal moment in modern nanotechnology.  Unknown to Don and the rest of IBM team though (I assume), they were pipped to the “nano” post a full ten years earlier… by an Italian sparkling wine… Continue reading “Nano” from the 1970’s. Don Eigler, eat your heart out!

Industry critics give nanotechnology sunscreens the thumbs up

The Environmental Working Group (EWG) – a US-based non-profit organization committed to using public information to protect public health and the environment – has just released what is probably the most comprehensive evaluation to date of the safety and effectiveness of using titanium dioxide and zinc oxide nanoparticles in sunscreens.  And their conclusion?

On balance, EWG researchers found that zinc and titanium-based formulations are among the safest, most effective sunscreens on the market based on available evidence.

In other words, not only are zinc oxide and titanium oxide nanoparticle-based sunscreens OK, but they are safer and more effective than many non nanotechnology-enabled sunscreens.

What makes this statement so startling is that EWG is not known for treating regulators and industry with kid gloves.  This is how the organization describes it’s way of working:

Our research brings to light unsettling facts that you have a right to know. It shames and shakes up polluters and their lobbyists. It rattles politicians and shapes policy. It persuades bureaucracies to rethink science and strengthen regulation.

EWG is about as far as you can get from a bunch of industry lackeys.  Yet here they are endorsing one of the more controversial products of nanotechnology… Continue reading Industry critics give nanotechnology sunscreens the thumbs up

Carbon nanotubes rock—literally!

A nanotechnology fix for high-end audio addicts?

I’m sitting at my computer watching a surreal balletic movie—a sheet of highly aligned carbon nanotubes is being slowly stretched, then allowed to slowly contract.  In the background is a soundtrack of traditional-sounding Chinese music.

At least I think the soundtrack is over-dubbed, until I realize that the music is coming directly from the nanotube sheet itself, which has been attached to a small amplifier.

And it suddenly dawns on me that I am watching something rather special—perhaps the biggest breakthrough in loudspeaker technology in decades… Continue reading Carbon nanotubes rock—literally!

Nanotechnology and cosmetics

UK Consumer Organization Which? Releases New Report

Who needs an emerging technologies blog when you have The Daily Mail?  For those of you that missed it, Wednesday’s on-line issue of the British tabloid newspaper highlighted

“The beauty creams with nanoparticles that could poison your body”

I’m so glad someone’s tracking this issue, while us folks over on the other side of the pond are dealing with the considerably less-interesting issues surrounding the incoming Obama administration.  The only trouble is, the Mail didn’t quite get it right.  In fact on a scale of 1 – 10, I’m not even sure they even make it to first base… Continue reading Nanotechnology and cosmetics